1. Technical Field
The present invention relates to a method for manufacturing a polymer alloy having a phase-separated structure consisting of at least two components, polymer alloy pellets, a polymer alloy film or sheet, a molded polymer alloy article, a polymer alloy containing polybutylene terephthalate resin and a polycarbonate resin, and a polymer alloy containing polyphenylene sulfide resin and a polyester resin with polyethylene terephthalate as a main component.
2. Background Art
JP5-156141A describes a molded article having a inter penetrating network structure obtained by melt blending polybutylene terephthalate resin, a polycarbonate resin, and acrylic graft (co)polymer particles. It is disclosed that this structure improves chemicals resistance, strength and toughness to some extent compared with a simple polymer alloy. However, according to the method described in the document, satisfactory effects could not be achieved in improving the strength, toughness and heat resistance of the molded article.
JP59-58052A discloses a composition consisting of PPS resin and a thermoplastic polyester resin, and further teaches a method of mixing an epoxy resin for further enhancing miscibility. However, according to the method described in the document, it was difficult to control the dispersion size for making it small. In order to obtain a molded article having excellent strength, toughness and heat resistance, a structure with a smaller dispersion size is desired. Furthermore, if the dispersion size in a polymer alloy is large, there arise such problems that in the case where the polymer alloy is used as fibers, the spinning stability during spinning is poor, and that voids are formed during stretching, to make the fibers fragile. Therefore, a method capable of controlling the structure for making it finer is desired.
JP8-113829A describes polymer blend fibers having a dispersed structure with a dispersion size of 0.001 to 0.4 μm formed in the cross section of each fiber, by melt-spinning a blend of polymers miscible with each other on the molecular level in a specific temperature range, in its miscible state, into fibers, and, for example, heat-treating the fibers for causing spinodal decomposition or nucleation and growth, to thereby cause phase decomposition. However, according to the method described in the document, because of the mechanism, in which the fibers obtained by spinning a polymer blend in its miscible state are heat-treated for causing phase separation, there was a limit in controlling the structure for making it finely dispersed. Furthermore, there was a limit in applicable combinations of polymers, and the form of the polymer blend was also limited to fibers.
To allow production of a molded article with excellent strength, toughness and heat resistance, a polymer alloy having excellent regularity and a homogeneously dispersed fine structure is demanded. A method for manufacturing it is also demanded. Furthermore, a manufacturing method applicable to combinations of immiscible polymers, hence for more general purposes is also demanded.
The problem to be solved by this invention is to provide a polymer alloy having excellent regularity and excellent mechanical properties, useful as a structural material or a functional material and capable of being controlled to have a structure on the order of nanometers or on the order of micrometers. It is also intended to provide a method for manufacturing the polymer alloy.